To talk about someone's ability (or inability) to do somethingexample: "We can find your house without the street plan." "She can't have a daughter that old!"

To talk about an action that is necessary (or impossible, or not necessary)example: "You must always have your driver's licence when you are driving your car." "You needn't carry your passport around with you."

To talk about a situation that is possible (or impossible)example: "Do be careful with that glass, the baby might knock it over"

A modal verb always has the same form:

There is no past form (-ed), no present participle (-ing) and no 3rd persons singular (-s).

Modal verbs come before the subject in questions:

example: "May I come to your house for tea?"

Negative forms:

Modal verbs have n't or not after them in the negative. example: "mustn't" - "needn't".

PRESENT FORM

PAST FORM

can

could

may

might

will

would

shall

should

must

-

ought to

-

need

-

Modal Forms

Listed below is a general outline of modal forms and their possible time reference.

Examples

Form

Time Reference

He can answer your question.They should leave early tomorrow.He had to leave at 7 this morning.

MODAL Simple Verb

Present

Future

Past

He might be joking!

Modal Continuous Form

Present

She can't have been serious!

They might have gone to the country.

Modal Verbs Present Perfect

Past

They might have been working at that time

Modal Present Perfect Continuous Verb

Past

Modal verbs can be confusing for many students. This quick guide and follow-up quizzes will help you understand the basics of modal verbs. After studying the following chart, try these challenging modal verb quizzes listed at the bottom of this page.

·Could do something -> It's possible for someone to do something.

·Must do something -> It's absolutely necessary for someone to do something.

·Need to do something -> It's important to do something.

·Have to do something -> It's absolutely necessary for someone to do something and someone else requires it.

·Mustn't do something -> It's forbidden for someone to do something.

·Couldn't do something -> Someone is unable to do something.

·Don't have to do something -> It isn't necessary for someone to do something.

·Shouldn't do something -> It isn't a good idea for someone to do something.

·Should do something -> It's a good idea for someone to do something.

·Might do something -> It's a possibility that someone might do something.